Data science enhances people’s decision making. Doctors and researchers are making critical decisions every day. Therefore, it is absolutely necessary for those people to have some basic knowledge of data science. This series aims to help people that are around medical field to enhance their data science skills. We will work with a health related […]

# statistics

## Multiple Regression (Part 2) – Diagnostics

Multiple Regression is one of the most widely used methods in statistical modelling. However, despite its many benefits, it is oftentimes used without checking the underlying assumptions. This can lead to results which can be misleading or even completely wrong. Therefore, applying diagnostics to detect any strong violations of the assumptions is important. In the […]

## Multiple Regression (Part 1)

In the exercises below we cover some material on multiple regression in R. Answers to the exercises are available here. If you obtained a different (correct) answer than those listed on the solutions page, please feel free to post your answer as a comment on that page. We will be using the dataset state.x77, which […]

## Intermediate Tree 2

This is a continuation of the intermediate decision tree exercise. Answers to the exercises are available here. If you obtained a different (correct) answer than those listed on the solutions page, please feel free to post your answer as a comment on that page. Exercise 1 use the predict() command to make predictions on […]

## Protected: ROC curves

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## Intermediate Tree 1

If you followed through the Basic Decision Tree exercise, this should be useful for you. This is like a continuation but we add so much more. We are working with a bigger and badder datasets. We will be also using techniques we learned from model evaluation and work with ROC, accuracy and other metrics. Answers […]

## Model Evaluation 2

We are committed to bringing you 100% authentic exercise sets. We even try to include as different datasets as possible to give you an understanding of different problems. No more classifying Titanic dataset. R has tons of datasets in its library. This is to encourage you to try as many datasets as possible. We will […]

## Basic Tree 2 Exercises

This is a continuation of the exercise Basic Tree 1 Answers to the exercises are available here. If you obtained a different (correct) answer than those listed on the solutions page, please feel free to post your answer as a comment on that page. Exercise 1 load the tree library. If it is not installed […]

## Recursive Partitioning and Regression Trees Exercises

[For this exercise, we will work using the package rpart. This is a beginner level exercise. Please refer to the help of rpart package] Answers to the exercises are available here. Exercise 1 Consider the Kyphosis data frame(type help(‘kyphosis’) for more details), that contains: -Kyphosis:a factor with levels absent present indicating if a kyphosis (a […]

## Basic Tree 1 Exercises

Using the knowledge you acquired in the previous exercises on sampling and selecting(here), we will now go through an entire data analysis process. You will be using what you know as crutches to solve the problems. Don’t worry. It might look intimidating but follow the sequence and you will see that modeling a decision tree […]